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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Purna Chandra Mandal,<purna.mandal@microchip.com>
4 * Copyright (C) 2015 Microchip Technology Inc. All rights reserved.
5 */
6#include <linux/clk-provider.h>
7#include <linux/delay.h>
8#include <linux/device.h>
9#include <linux/interrupt.h>
10#include <linux/io.h>
11#include <linux/iopoll.h>
12#include <asm/mach-pic32/pic32.h>
13#include <asm/traps.h>
14
15#include "clk-core.h"
16
17/* OSCCON Reg fields */
18#define OSC_CUR_MASK 0x07
19#define OSC_CUR_SHIFT 12
20#define OSC_NEW_MASK 0x07
21#define OSC_NEW_SHIFT 8
22#define OSC_SWEN BIT(0)
23
24/* SPLLCON Reg fields */
25#define PLL_RANGE_MASK 0x07
26#define PLL_RANGE_SHIFT 0
27#define PLL_ICLK_MASK 0x01
28#define PLL_ICLK_SHIFT 7
29#define PLL_IDIV_MASK 0x07
30#define PLL_IDIV_SHIFT 8
31#define PLL_ODIV_MASK 0x07
32#define PLL_ODIV_SHIFT 24
33#define PLL_MULT_MASK 0x7F
34#define PLL_MULT_SHIFT 16
35#define PLL_MULT_MAX 128
36#define PLL_ODIV_MIN 1
37#define PLL_ODIV_MAX 5
38
39/* Peripheral Bus Clock Reg Fields */
40#define PB_DIV_MASK 0x7f
41#define PB_DIV_SHIFT 0
42#define PB_DIV_READY BIT(11)
43#define PB_DIV_ENABLE BIT(15)
44#define PB_DIV_MAX 128
45#define PB_DIV_MIN 0
46
47/* Reference Oscillator Control Reg fields */
48#define REFO_SEL_MASK 0x0f
49#define REFO_SEL_SHIFT 0
50#define REFO_ACTIVE BIT(8)
51#define REFO_DIVSW_EN BIT(9)
52#define REFO_OE BIT(12)
53#define REFO_ON BIT(15)
54#define REFO_DIV_SHIFT 16
55#define REFO_DIV_MASK 0x7fff
56
57/* Reference Oscillator Trim Register Fields */
58#define REFO_TRIM_REG 0x10
59#define REFO_TRIM_MASK 0x1ff
60#define REFO_TRIM_SHIFT 23
61#define REFO_TRIM_MAX 511
62
63/* Mux Slew Control Register fields */
64#define SLEW_BUSY BIT(0)
65#define SLEW_DOWNEN BIT(1)
66#define SLEW_UPEN BIT(2)
67#define SLEW_DIV 0x07
68#define SLEW_DIV_SHIFT 8
69#define SLEW_SYSDIV 0x0f
70#define SLEW_SYSDIV_SHIFT 20
71
72/* Clock Poll Timeout */
73#define LOCK_TIMEOUT_US USEC_PER_MSEC
74
75/* SoC specific clock needed during SPLL clock rate switch */
76static struct clk_hw *pic32_sclk_hw;
77
78/* add instruction pipeline delay while CPU clock is in-transition. */
79#define cpu_nop5() \
80do { \
81 __asm__ __volatile__("nop"); \
82 __asm__ __volatile__("nop"); \
83 __asm__ __volatile__("nop"); \
84 __asm__ __volatile__("nop"); \
85 __asm__ __volatile__("nop"); \
86} while (0)
87
88/* Perpheral bus clocks */
89struct pic32_periph_clk {
90 struct clk_hw hw;
91 void __iomem *ctrl_reg;
92 struct pic32_clk_common *core;
93};
94
95#define clkhw_to_pbclk(_hw) container_of(_hw, struct pic32_periph_clk, hw)
96
97static int pbclk_is_enabled(struct clk_hw *hw)
98{
99 struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
100
101 return readl(pb->ctrl_reg) & PB_DIV_ENABLE;
102}
103
104static int pbclk_enable(struct clk_hw *hw)
105{
106 struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
107
108 writel(PB_DIV_ENABLE, PIC32_SET(pb->ctrl_reg));
109 return 0;
110}
111
112static void pbclk_disable(struct clk_hw *hw)
113{
114 struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
115
116 writel(PB_DIV_ENABLE, PIC32_CLR(pb->ctrl_reg));
117}
118
119static unsigned long calc_best_divided_rate(unsigned long rate,
120 unsigned long parent_rate,
121 u32 divider_max,
122 u32 divider_min)
123{
124 unsigned long divided_rate, divided_rate_down, best_rate;
125 unsigned long div, div_up;
126
127 /* eq. clk_rate = parent_rate / divider.
128 *
129 * Find best divider to produce closest of target divided rate.
130 */
131 div = parent_rate / rate;
132 div = clamp_val(div, divider_min, divider_max);
133 div_up = clamp_val(div + 1, divider_min, divider_max);
134
135 divided_rate = parent_rate / div;
136 divided_rate_down = parent_rate / div_up;
137 if (abs(rate - divided_rate_down) < abs(rate - divided_rate))
138 best_rate = divided_rate_down;
139 else
140 best_rate = divided_rate;
141
142 return best_rate;
143}
144
145static inline u32 pbclk_read_pbdiv(struct pic32_periph_clk *pb)
146{
147 return ((readl(pb->ctrl_reg) >> PB_DIV_SHIFT) & PB_DIV_MASK) + 1;
148}
149
150static unsigned long pbclk_recalc_rate(struct clk_hw *hw,
151 unsigned long parent_rate)
152{
153 struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
154
155 return parent_rate / pbclk_read_pbdiv(pb);
156}
157
158static long pbclk_round_rate(struct clk_hw *hw, unsigned long rate,
159 unsigned long *parent_rate)
160{
161 return calc_best_divided_rate(rate, *parent_rate,
162 PB_DIV_MAX, PB_DIV_MIN);
163}
164
165static int pbclk_set_rate(struct clk_hw *hw, unsigned long rate,
166 unsigned long parent_rate)
167{
168 struct pic32_periph_clk *pb = clkhw_to_pbclk(hw);
169 unsigned long flags;
170 u32 v, div;
171 int err;
172
173 /* check & wait for DIV_READY */
174 err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
175 1, LOCK_TIMEOUT_US);
176 if (err)
177 return err;
178
179 /* calculate clkdiv and best rate */
180 div = DIV_ROUND_CLOSEST(parent_rate, rate);
181
182 spin_lock_irqsave(&pb->core->reg_lock, flags);
183
184 /* apply new div */
185 v = readl(pb->ctrl_reg);
186 v &= ~PB_DIV_MASK;
187 v |= (div - 1);
188
189 pic32_syskey_unlock();
190
191 writel(v, pb->ctrl_reg);
192
193 spin_unlock_irqrestore(&pb->core->reg_lock, flags);
194
195 /* wait again for DIV_READY */
196 err = readl_poll_timeout(pb->ctrl_reg, v, v & PB_DIV_READY,
197 1, LOCK_TIMEOUT_US);
198 if (err)
199 return err;
200
201 /* confirm that new div is applied correctly */
202 return (pbclk_read_pbdiv(pb) == div) ? 0 : -EBUSY;
203}
204
205const struct clk_ops pic32_pbclk_ops = {
206 .enable = pbclk_enable,
207 .disable = pbclk_disable,
208 .is_enabled = pbclk_is_enabled,
209 .recalc_rate = pbclk_recalc_rate,
210 .round_rate = pbclk_round_rate,
211 .set_rate = pbclk_set_rate,
212};
213
214struct clk *pic32_periph_clk_register(const struct pic32_periph_clk_data *desc,
215 struct pic32_clk_common *core)
216{
217 struct pic32_periph_clk *pbclk;
218 struct clk *clk;
219
220 pbclk = devm_kzalloc(core->dev, sizeof(*pbclk), GFP_KERNEL);
221 if (!pbclk)
222 return ERR_PTR(-ENOMEM);
223
224 pbclk->hw.init = &desc->init_data;
225 pbclk->core = core;
226 pbclk->ctrl_reg = desc->ctrl_reg + core->iobase;
227
228 clk = devm_clk_register(core->dev, &pbclk->hw);
229 if (IS_ERR(clk)) {
230 dev_err(core->dev, "%s: clk_register() failed\n", __func__);
231 devm_kfree(core->dev, pbclk);
232 }
233
234 return clk;
235}
236
237/* Reference oscillator operations */
238struct pic32_ref_osc {
239 struct clk_hw hw;
240 void __iomem *ctrl_reg;
241 const u32 *parent_map;
242 struct pic32_clk_common *core;
243};
244
245#define clkhw_to_refosc(_hw) container_of(_hw, struct pic32_ref_osc, hw)
246
247static int roclk_is_enabled(struct clk_hw *hw)
248{
249 struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
250
251 return readl(refo->ctrl_reg) & REFO_ON;
252}
253
254static int roclk_enable(struct clk_hw *hw)
255{
256 struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
257
258 writel(REFO_ON | REFO_OE, PIC32_SET(refo->ctrl_reg));
259 return 0;
260}
261
262static void roclk_disable(struct clk_hw *hw)
263{
264 struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
265
266 writel(REFO_ON | REFO_OE, PIC32_CLR(refo->ctrl_reg));
267}
268
269static int roclk_init(struct clk_hw *hw)
270{
271 /* initialize clock in disabled state */
272 roclk_disable(hw);
273
274 return 0;
275}
276
277static u8 roclk_get_parent(struct clk_hw *hw)
278{
279 struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
280 u32 v, i;
281
282 v = (readl(refo->ctrl_reg) >> REFO_SEL_SHIFT) & REFO_SEL_MASK;
283
284 if (!refo->parent_map)
285 return v;
286
287 for (i = 0; i < clk_hw_get_num_parents(hw); i++)
288 if (refo->parent_map[i] == v)
289 return i;
290
291 return -EINVAL;
292}
293
294static unsigned long roclk_calc_rate(unsigned long parent_rate,
295 u32 rodiv, u32 rotrim)
296{
297 u64 rate64;
298
299 /* fout = fin / [2 * {div + (trim / 512)}]
300 * = fin * 512 / [1024 * div + 2 * trim]
301 * = fin * 256 / (512 * div + trim)
302 * = (fin << 8) / ((div << 9) + trim)
303 */
304 if (rotrim) {
305 rodiv = (rodiv << 9) + rotrim;
306 rate64 = parent_rate;
307 rate64 <<= 8;
308 do_div(rate64, rodiv);
309 } else if (rodiv) {
310 rate64 = parent_rate / (rodiv << 1);
311 } else {
312 rate64 = parent_rate;
313 }
314 return rate64;
315}
316
317static void roclk_calc_div_trim(unsigned long rate,
318 unsigned long parent_rate,
319 u32 *rodiv_p, u32 *rotrim_p)
320{
321 u32 div, rotrim, rodiv;
322 u64 frac;
323
324 /* Find integer approximation of floating-point arithmetic.
325 * fout = fin / [2 * {rodiv + (rotrim / 512)}] ... (1)
326 * i.e. fout = fin / 2 * DIV
327 * whereas DIV = rodiv + (rotrim / 512)
328 *
329 * Since kernel does not perform floating-point arithmatic so
330 * (rotrim/512) will be zero. And DIV & rodiv will result same.
331 *
332 * ie. fout = (fin * 256) / [(512 * rodiv) + rotrim] ... from (1)
333 * ie. rotrim = ((fin * 256) / fout) - (512 * DIV)
334 */
335 if (parent_rate <= rate) {
336 div = 0;
337 frac = 0;
338 rodiv = 0;
339 rotrim = 0;
340 } else {
341 div = parent_rate / (rate << 1);
342 frac = parent_rate;
343 frac <<= 8;
344 do_div(frac, rate);
345 frac -= (u64)(div << 9);
346
347 rodiv = (div > REFO_DIV_MASK) ? REFO_DIV_MASK : div;
348 rotrim = (frac >= REFO_TRIM_MAX) ? REFO_TRIM_MAX : frac;
349 }
350
351 if (rodiv_p)
352 *rodiv_p = rodiv;
353
354 if (rotrim_p)
355 *rotrim_p = rotrim;
356}
357
358static unsigned long roclk_recalc_rate(struct clk_hw *hw,
359 unsigned long parent_rate)
360{
361 struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
362 u32 v, rodiv, rotrim;
363
364 /* get rodiv */
365 v = readl(refo->ctrl_reg);
366 rodiv = (v >> REFO_DIV_SHIFT) & REFO_DIV_MASK;
367
368 /* get trim */
369 v = readl(refo->ctrl_reg + REFO_TRIM_REG);
370 rotrim = (v >> REFO_TRIM_SHIFT) & REFO_TRIM_MASK;
371
372 return roclk_calc_rate(parent_rate, rodiv, rotrim);
373}
374
375static long roclk_round_rate(struct clk_hw *hw, unsigned long rate,
376 unsigned long *parent_rate)
377{
378 u32 rotrim, rodiv;
379
380 /* calculate dividers for new rate */
381 roclk_calc_div_trim(rate, *parent_rate, &rodiv, &rotrim);
382
383 /* caclulate new rate (rounding) based on new rodiv & rotrim */
384 return roclk_calc_rate(*parent_rate, rodiv, rotrim);
385}
386
387static int roclk_determine_rate(struct clk_hw *hw,
388 struct clk_rate_request *req)
389{
390 struct clk_hw *parent_clk, *best_parent_clk = NULL;
391 unsigned int i, delta, best_delta = -1;
392 unsigned long parent_rate, best_parent_rate = 0;
393 unsigned long best = 0, nearest_rate;
394
395 /* find a parent which can generate nearest clkrate >= rate */
396 for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
397 /* get parent */
398 parent_clk = clk_hw_get_parent_by_index(hw, i);
399 if (!parent_clk)
400 continue;
401
402 /* skip if parent runs slower than target rate */
403 parent_rate = clk_hw_get_rate(parent_clk);
404 if (req->rate > parent_rate)
405 continue;
406
407 nearest_rate = roclk_round_rate(hw, req->rate, &parent_rate);
408 delta = abs(nearest_rate - req->rate);
409 if ((nearest_rate >= req->rate) && (delta < best_delta)) {
410 best_parent_clk = parent_clk;
411 best_parent_rate = parent_rate;
412 best = nearest_rate;
413 best_delta = delta;
414
415 if (delta == 0)
416 break;
417 }
418 }
419
420 /* if no match found, retain old rate */
421 if (!best_parent_clk) {
422 pr_err("%s:%s, no parent found for rate %lu.\n",
423 __func__, clk_hw_get_name(hw), req->rate);
424 return clk_hw_get_rate(hw);
425 }
426
427 pr_debug("%s,rate %lu, best_parent(%s, %lu), best %lu, delta %d\n",
428 clk_hw_get_name(hw), req->rate,
429 clk_hw_get_name(best_parent_clk), best_parent_rate,
430 best, best_delta);
431
432 if (req->best_parent_rate)
433 req->best_parent_rate = best_parent_rate;
434
435 if (req->best_parent_hw)
436 req->best_parent_hw = best_parent_clk;
437
438 return best;
439}
440
441static int roclk_set_parent(struct clk_hw *hw, u8 index)
442{
443 struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
444 unsigned long flags;
445 u32 v;
446 int err;
447
448 if (refo->parent_map)
449 index = refo->parent_map[index];
450
451 /* wait until ACTIVE bit is zero or timeout */
452 err = readl_poll_timeout(refo->ctrl_reg, v, !(v & REFO_ACTIVE),
453 1, LOCK_TIMEOUT_US);
454 if (err) {
455 pr_err("%s: poll failed, clk active\n", clk_hw_get_name(hw));
456 return err;
457 }
458
459 spin_lock_irqsave(&refo->core->reg_lock, flags);
460
461 pic32_syskey_unlock();
462
463 /* calculate & apply new */
464 v = readl(refo->ctrl_reg);
465 v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
466 v |= index << REFO_SEL_SHIFT;
467
468 writel(v, refo->ctrl_reg);
469
470 spin_unlock_irqrestore(&refo->core->reg_lock, flags);
471
472 return 0;
473}
474
475static int roclk_set_rate_and_parent(struct clk_hw *hw,
476 unsigned long rate,
477 unsigned long parent_rate,
478 u8 index)
479{
480 struct pic32_ref_osc *refo = clkhw_to_refosc(hw);
481 unsigned long flags;
482 u32 trim, rodiv, v;
483 int err;
484
485 /* calculate new rodiv & rotrim for new rate */
486 roclk_calc_div_trim(rate, parent_rate, &rodiv, &trim);
487
488 pr_debug("parent_rate = %lu, rate = %lu, div = %d, trim = %d\n",
489 parent_rate, rate, rodiv, trim);
490
491 /* wait till source change is active */
492 err = readl_poll_timeout(refo->ctrl_reg, v,
493 !(v & (REFO_ACTIVE | REFO_DIVSW_EN)),
494 1, LOCK_TIMEOUT_US);
495 if (err) {
496 pr_err("%s: poll timedout, clock is still active\n", __func__);
497 return err;
498 }
499
500 spin_lock_irqsave(&refo->core->reg_lock, flags);
501 v = readl(refo->ctrl_reg);
502
503 pic32_syskey_unlock();
504
505 /* apply parent, if required */
506 if (refo->parent_map)
507 index = refo->parent_map[index];
508
509 v &= ~(REFO_SEL_MASK << REFO_SEL_SHIFT);
510 v |= index << REFO_SEL_SHIFT;
511
512 /* apply RODIV */
513 v &= ~(REFO_DIV_MASK << REFO_DIV_SHIFT);
514 v |= rodiv << REFO_DIV_SHIFT;
515 writel(v, refo->ctrl_reg);
516
517 /* apply ROTRIM */
518 v = readl(refo->ctrl_reg + REFO_TRIM_REG);
519 v &= ~(REFO_TRIM_MASK << REFO_TRIM_SHIFT);
520 v |= trim << REFO_TRIM_SHIFT;
521 writel(v, refo->ctrl_reg + REFO_TRIM_REG);
522
523 /* enable & activate divider switching */
524 writel(REFO_ON | REFO_DIVSW_EN, PIC32_SET(refo->ctrl_reg));
525
526 /* wait till divswen is in-progress */
527 err = readl_poll_timeout_atomic(refo->ctrl_reg, v, !(v & REFO_DIVSW_EN),
528 1, LOCK_TIMEOUT_US);
529 /* leave the clk gated as it was */
530 writel(REFO_ON, PIC32_CLR(refo->ctrl_reg));
531
532 spin_unlock_irqrestore(&refo->core->reg_lock, flags);
533
534 return err;
535}
536
537static int roclk_set_rate(struct clk_hw *hw, unsigned long rate,
538 unsigned long parent_rate)
539{
540 u8 index = roclk_get_parent(hw);
541
542 return roclk_set_rate_and_parent(hw, rate, parent_rate, index);
543}
544
545const struct clk_ops pic32_roclk_ops = {
546 .enable = roclk_enable,
547 .disable = roclk_disable,
548 .is_enabled = roclk_is_enabled,
549 .get_parent = roclk_get_parent,
550 .set_parent = roclk_set_parent,
551 .determine_rate = roclk_determine_rate,
552 .recalc_rate = roclk_recalc_rate,
553 .set_rate_and_parent = roclk_set_rate_and_parent,
554 .set_rate = roclk_set_rate,
555 .init = roclk_init,
556};
557
558struct clk *pic32_refo_clk_register(const struct pic32_ref_osc_data *data,
559 struct pic32_clk_common *core)
560{
561 struct pic32_ref_osc *refo;
562 struct clk *clk;
563
564 refo = devm_kzalloc(core->dev, sizeof(*refo), GFP_KERNEL);
565 if (!refo)
566 return ERR_PTR(-ENOMEM);
567
568 refo->core = core;
569 refo->hw.init = &data->init_data;
570 refo->ctrl_reg = data->ctrl_reg + core->iobase;
571 refo->parent_map = data->parent_map;
572
573 clk = devm_clk_register(core->dev, &refo->hw);
574 if (IS_ERR(clk))
575 dev_err(core->dev, "%s: clk_register() failed\n", __func__);
576
577 return clk;
578}
579
580struct pic32_sys_pll {
581 struct clk_hw hw;
582 void __iomem *ctrl_reg;
583 void __iomem *status_reg;
584 u32 lock_mask;
585 u32 idiv; /* PLL iclk divider, treated fixed */
586 struct pic32_clk_common *core;
587};
588
589#define clkhw_to_spll(_hw) container_of(_hw, struct pic32_sys_pll, hw)
590
591static inline u32 spll_odiv_to_divider(u32 odiv)
592{
593 odiv = clamp_val(odiv, PLL_ODIV_MIN, PLL_ODIV_MAX);
594
595 return 1 << odiv;
596}
597
598static unsigned long spll_calc_mult_div(struct pic32_sys_pll *pll,
599 unsigned long rate,
600 unsigned long parent_rate,
601 u32 *mult_p, u32 *odiv_p)
602{
603 u32 mul, div, best_mul = 1, best_div = 1;
604 unsigned long new_rate, best_rate = rate;
605 unsigned int best_delta = -1, delta, match_found = 0;
606 u64 rate64;
607
608 parent_rate /= pll->idiv;
609
610 for (mul = 1; mul <= PLL_MULT_MAX; mul++) {
611 for (div = PLL_ODIV_MIN; div <= PLL_ODIV_MAX; div++) {
612 rate64 = parent_rate;
613 rate64 *= mul;
614 do_div(rate64, 1 << div);
615 new_rate = rate64;
616 delta = abs(rate - new_rate);
617 if ((new_rate >= rate) && (delta < best_delta)) {
618 best_delta = delta;
619 best_rate = new_rate;
620 best_mul = mul;
621 best_div = div;
622 match_found = 1;
623 }
624 }
625 }
626
627 if (!match_found) {
628 pr_warn("spll: no match found\n");
629 return 0;
630 }
631
632 pr_debug("rate %lu, par_rate %lu/mult %u, div %u, best_rate %lu\n",
633 rate, parent_rate, best_mul, best_div, best_rate);
634
635 if (mult_p)
636 *mult_p = best_mul - 1;
637
638 if (odiv_p)
639 *odiv_p = best_div;
640
641 return best_rate;
642}
643
644static unsigned long spll_clk_recalc_rate(struct clk_hw *hw,
645 unsigned long parent_rate)
646{
647 struct pic32_sys_pll *pll = clkhw_to_spll(hw);
648 unsigned long pll_in_rate;
649 u32 mult, odiv, div, v;
650 u64 rate64;
651
652 v = readl(pll->ctrl_reg);
653 odiv = ((v >> PLL_ODIV_SHIFT) & PLL_ODIV_MASK);
654 mult = ((v >> PLL_MULT_SHIFT) & PLL_MULT_MASK) + 1;
655 div = spll_odiv_to_divider(odiv);
656
657 /* pll_in_rate = parent_rate / idiv
658 * pll_out_rate = pll_in_rate * mult / div;
659 */
660 pll_in_rate = parent_rate / pll->idiv;
661 rate64 = pll_in_rate;
662 rate64 *= mult;
663 do_div(rate64, div);
664
665 return rate64;
666}
667
668static long spll_clk_round_rate(struct clk_hw *hw, unsigned long rate,
669 unsigned long *parent_rate)
670{
671 struct pic32_sys_pll *pll = clkhw_to_spll(hw);
672
673 return spll_calc_mult_div(pll, rate, *parent_rate, NULL, NULL);
674}
675
676static int spll_clk_set_rate(struct clk_hw *hw, unsigned long rate,
677 unsigned long parent_rate)
678{
679 struct pic32_sys_pll *pll = clkhw_to_spll(hw);
680 unsigned long ret, flags;
681 u32 mult, odiv, v;
682 int err;
683
684 ret = spll_calc_mult_div(pll, rate, parent_rate, &mult, &odiv);
685 if (!ret)
686 return -EINVAL;
687
688 /*
689 * We can't change SPLL counters when it is in-active use
690 * by SYSCLK. So check before applying new counters/rate.
691 */
692
693 /* Is spll_clk active parent of sys_clk ? */
694 if (unlikely(clk_hw_get_parent(pic32_sclk_hw) == hw)) {
695 pr_err("%s: failed, clk in-use\n", __func__);
696 return -EBUSY;
697 }
698
699 spin_lock_irqsave(&pll->core->reg_lock, flags);
700
701 /* apply new multiplier & divisor */
702 v = readl(pll->ctrl_reg);
703 v &= ~(PLL_MULT_MASK << PLL_MULT_SHIFT);
704 v &= ~(PLL_ODIV_MASK << PLL_ODIV_SHIFT);
705 v |= (mult << PLL_MULT_SHIFT) | (odiv << PLL_ODIV_SHIFT);
706
707 /* sys unlock before write */
708 pic32_syskey_unlock();
709
710 writel(v, pll->ctrl_reg);
711 cpu_relax();
712
713 /* insert few nops (5-stage) to ensure CPU does not hang */
714 cpu_nop5();
715 cpu_nop5();
716
717 /* Wait until PLL is locked (maximum 100 usecs). */
718 err = readl_poll_timeout_atomic(pll->status_reg, v,
719 v & pll->lock_mask, 1, 100);
720 spin_unlock_irqrestore(&pll->core->reg_lock, flags);
721
722 return err;
723}
724
725/* SPLL clock operation */
726const struct clk_ops pic32_spll_ops = {
727 .recalc_rate = spll_clk_recalc_rate,
728 .round_rate = spll_clk_round_rate,
729 .set_rate = spll_clk_set_rate,
730};
731
732struct clk *pic32_spll_clk_register(const struct pic32_sys_pll_data *data,
733 struct pic32_clk_common *core)
734{
735 struct pic32_sys_pll *spll;
736 struct clk *clk;
737
738 spll = devm_kzalloc(core->dev, sizeof(*spll), GFP_KERNEL);
739 if (!spll)
740 return ERR_PTR(-ENOMEM);
741
742 spll->core = core;
743 spll->hw.init = &data->init_data;
744 spll->ctrl_reg = data->ctrl_reg + core->iobase;
745 spll->status_reg = data->status_reg + core->iobase;
746 spll->lock_mask = data->lock_mask;
747
748 /* cache PLL idiv; PLL driver uses it as constant.*/
749 spll->idiv = (readl(spll->ctrl_reg) >> PLL_IDIV_SHIFT) & PLL_IDIV_MASK;
750 spll->idiv += 1;
751
752 clk = devm_clk_register(core->dev, &spll->hw);
753 if (IS_ERR(clk))
754 dev_err(core->dev, "sys_pll: clk_register() failed\n");
755
756 return clk;
757}
758
759/* System mux clock(aka SCLK) */
760
761struct pic32_sys_clk {
762 struct clk_hw hw;
763 void __iomem *mux_reg;
764 void __iomem *slew_reg;
765 u32 slew_div;
766 const u32 *parent_map;
767 struct pic32_clk_common *core;
768};
769
770#define clkhw_to_sys_clk(_hw) container_of(_hw, struct pic32_sys_clk, hw)
771
772static unsigned long sclk_get_rate(struct clk_hw *hw, unsigned long parent_rate)
773{
774 struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
775 u32 div;
776
777 div = (readl(sclk->slew_reg) >> SLEW_SYSDIV_SHIFT) & SLEW_SYSDIV;
778 div += 1; /* sys-div to divider */
779
780 return parent_rate / div;
781}
782
783static long sclk_round_rate(struct clk_hw *hw, unsigned long rate,
784 unsigned long *parent_rate)
785{
786 return calc_best_divided_rate(rate, *parent_rate, SLEW_SYSDIV, 1);
787}
788
789static int sclk_set_rate(struct clk_hw *hw,
790 unsigned long rate, unsigned long parent_rate)
791{
792 struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
793 unsigned long flags;
794 u32 v, div;
795 int err;
796
797 div = parent_rate / rate;
798
799 spin_lock_irqsave(&sclk->core->reg_lock, flags);
800
801 /* apply new div */
802 v = readl(sclk->slew_reg);
803 v &= ~(SLEW_SYSDIV << SLEW_SYSDIV_SHIFT);
804 v |= (div - 1) << SLEW_SYSDIV_SHIFT;
805
806 pic32_syskey_unlock();
807
808 writel(v, sclk->slew_reg);
809
810 /* wait until BUSY is cleared */
811 err = readl_poll_timeout_atomic(sclk->slew_reg, v,
812 !(v & SLEW_BUSY), 1, LOCK_TIMEOUT_US);
813
814 spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
815
816 return err;
817}
818
819static u8 sclk_get_parent(struct clk_hw *hw)
820{
821 struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
822 u32 i, v;
823
824 v = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
825
826 if (!sclk->parent_map)
827 return v;
828
829 for (i = 0; i < clk_hw_get_num_parents(hw); i++)
830 if (sclk->parent_map[i] == v)
831 return i;
832 return -EINVAL;
833}
834
835static int sclk_set_parent(struct clk_hw *hw, u8 index)
836{
837 struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
838 unsigned long flags;
839 u32 nosc, cosc, v;
840 int err;
841
842 spin_lock_irqsave(&sclk->core->reg_lock, flags);
843
844 /* find new_osc */
845 nosc = sclk->parent_map ? sclk->parent_map[index] : index;
846
847 /* set new parent */
848 v = readl(sclk->mux_reg);
849 v &= ~(OSC_NEW_MASK << OSC_NEW_SHIFT);
850 v |= nosc << OSC_NEW_SHIFT;
851
852 pic32_syskey_unlock();
853
854 writel(v, sclk->mux_reg);
855
856 /* initate switch */
857 writel(OSC_SWEN, PIC32_SET(sclk->mux_reg));
858 cpu_relax();
859
860 /* add nop to flush pipeline (as cpu_clk is in-flux) */
861 cpu_nop5();
862
863 /* wait for SWEN bit to clear */
864 err = readl_poll_timeout_atomic(sclk->slew_reg, v,
865 !(v & OSC_SWEN), 1, LOCK_TIMEOUT_US);
866
867 spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
868
869 /*
870 * SCLK clock-switching logic might reject a clock switching request
871 * if pre-requisites (like new clk_src not present or unstable) are
872 * not met.
873 * So confirm before claiming success.
874 */
875 cosc = (readl(sclk->mux_reg) >> OSC_CUR_SHIFT) & OSC_CUR_MASK;
876 if (cosc != nosc) {
877 pr_err("%s: err, failed to set_parent() to %d, current %d\n",
878 clk_hw_get_name(hw), nosc, cosc);
879 err = -EBUSY;
880 }
881
882 return err;
883}
884
885static int sclk_init(struct clk_hw *hw)
886{
887 struct pic32_sys_clk *sclk = clkhw_to_sys_clk(hw);
888 unsigned long flags;
889 u32 v;
890
891 /* Maintain reference to this clk, required in spll_clk_set_rate() */
892 pic32_sclk_hw = hw;
893
894 /* apply slew divider on both up and down scaling */
895 if (sclk->slew_div) {
896 spin_lock_irqsave(&sclk->core->reg_lock, flags);
897 v = readl(sclk->slew_reg);
898 v &= ~(SLEW_DIV << SLEW_DIV_SHIFT);
899 v |= sclk->slew_div << SLEW_DIV_SHIFT;
900 v |= SLEW_DOWNEN | SLEW_UPEN;
901 writel(v, sclk->slew_reg);
902 spin_unlock_irqrestore(&sclk->core->reg_lock, flags);
903 }
904
905 return 0;
906}
907
908/* sclk with post-divider */
909const struct clk_ops pic32_sclk_ops = {
910 .get_parent = sclk_get_parent,
911 .set_parent = sclk_set_parent,
912 .round_rate = sclk_round_rate,
913 .set_rate = sclk_set_rate,
914 .recalc_rate = sclk_get_rate,
915 .init = sclk_init,
916 .determine_rate = __clk_mux_determine_rate,
917};
918
919/* sclk with no slew and no post-divider */
920const struct clk_ops pic32_sclk_no_div_ops = {
921 .get_parent = sclk_get_parent,
922 .set_parent = sclk_set_parent,
923 .init = sclk_init,
924 .determine_rate = __clk_mux_determine_rate,
925};
926
927struct clk *pic32_sys_clk_register(const struct pic32_sys_clk_data *data,
928 struct pic32_clk_common *core)
929{
930 struct pic32_sys_clk *sclk;
931 struct clk *clk;
932
933 sclk = devm_kzalloc(core->dev, sizeof(*sclk), GFP_KERNEL);
934 if (!sclk)
935 return ERR_PTR(-ENOMEM);
936
937 sclk->core = core;
938 sclk->hw.init = &data->init_data;
939 sclk->mux_reg = data->mux_reg + core->iobase;
940 sclk->slew_reg = data->slew_reg + core->iobase;
941 sclk->slew_div = data->slew_div;
942 sclk->parent_map = data->parent_map;
943
944 clk = devm_clk_register(core->dev, &sclk->hw);
945 if (IS_ERR(clk))
946 dev_err(core->dev, "%s: clk register failed\n", __func__);
947
948 return clk;
949}
950
951/* secondary oscillator */
952struct pic32_sec_osc {
953 struct clk_hw hw;
954 void __iomem *enable_reg;
955 void __iomem *status_reg;
956 u32 enable_mask;
957 u32 status_mask;
958 unsigned long fixed_rate;
959 struct pic32_clk_common *core;
960};
961
962#define clkhw_to_sosc(_hw) container_of(_hw, struct pic32_sec_osc, hw)
963static int sosc_clk_enable(struct clk_hw *hw)
964{
965 struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
966 u32 v;
967
968 /* enable SOSC */
969 pic32_syskey_unlock();
970 writel(sosc->enable_mask, PIC32_SET(sosc->enable_reg));
971
972 /* wait till warm-up period expires or ready-status is updated */
973 return readl_poll_timeout_atomic(sosc->status_reg, v,
974 v & sosc->status_mask, 1, 100);
975}
976
977static void sosc_clk_disable(struct clk_hw *hw)
978{
979 struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
980
981 pic32_syskey_unlock();
982 writel(sosc->enable_mask, PIC32_CLR(sosc->enable_reg));
983}
984
985static int sosc_clk_is_enabled(struct clk_hw *hw)
986{
987 struct pic32_sec_osc *sosc = clkhw_to_sosc(hw);
988 u32 enabled, ready;
989
990 /* check enabled and ready status */
991 enabled = readl(sosc->enable_reg) & sosc->enable_mask;
992 ready = readl(sosc->status_reg) & sosc->status_mask;
993
994 return enabled && ready;
995}
996
997static unsigned long sosc_clk_calc_rate(struct clk_hw *hw,
998 unsigned long parent_rate)
999{
1000 return clkhw_to_sosc(hw)->fixed_rate;
1001}
1002
1003const struct clk_ops pic32_sosc_ops = {
1004 .enable = sosc_clk_enable,
1005 .disable = sosc_clk_disable,
1006 .is_enabled = sosc_clk_is_enabled,
1007 .recalc_rate = sosc_clk_calc_rate,
1008};
1009
1010struct clk *pic32_sosc_clk_register(const struct pic32_sec_osc_data *data,
1011 struct pic32_clk_common *core)
1012{
1013 struct pic32_sec_osc *sosc;
1014
1015 sosc = devm_kzalloc(core->dev, sizeof(*sosc), GFP_KERNEL);
1016 if (!sosc)
1017 return ERR_PTR(-ENOMEM);
1018
1019 sosc->core = core;
1020 sosc->hw.init = &data->init_data;
1021 sosc->fixed_rate = data->fixed_rate;
1022 sosc->enable_mask = data->enable_mask;
1023 sosc->status_mask = data->status_mask;
1024 sosc->enable_reg = data->enable_reg + core->iobase;
1025 sosc->status_reg = data->status_reg + core->iobase;
1026
1027 return devm_clk_register(core->dev, &sosc->hw);
1028}